movable_block: fix bugs with falling blocks

Resolves #723.
Changes Room_AlterFloorHeight.

CHANGELOG.md

@@ -15,6 +15,7 @@
 - fixed 3d pickups sometimes triggering z-buffer issues (#1015)
 - fixed oversized passport in cinematic camera mode (eg when Lara steps on the Midas Hand) (#1009)
 - fixed braid being disabled by default unless the player runs the config tool first (#1043)
+- fixed various bugs with falling movable blocks (#723)
 - improved frame scheduling to use less CPU (#985)
 - improved and expanded gameflow documentation (#1018)
 - rotated the Scion in Tomb of Qualopec to face the the main gate and Qualopec (#1007)

README.md

@@ -295,6 +295,7 @@ Not all options are turned on by default. Refer to `TR1X_ConfigTool.exe` for det
     - **City of Khamoon**: incorrect trapdoor trigger types in rooms 31 and 34
     - **Obelisk of Khamoon**: missing switch trigger type in room 66
     - **Atlantean Stronghold**: fixed poorly configured portals between rooms 74 and 12
+- fixed various bugs with falling movable blocks
 
 #### Cheats
 - added a fly cheat

src/game/items.c

@@ -260,6 +260,17 @@ void Item_UpdateRoom(ITEM_INFO *item, int32_t height)
     }
 }
 
+int16_t Item_GetHeight(ITEM_INFO *item)
+{
+    int16_t room_num = item->room_number;
+    FLOOR_INFO *floor =
+        Room_GetFloor(item->pos.x, item->pos.y, item->pos.z, &room_num);
+    int32_t height =
+        Room_GetHeight(floor, item->pos.x, item->pos.y, item->pos.z);
+
+    return height;
+}
+
 int16_t Item_GetWaterHeight(ITEM_INFO *item)
 {
     int16_t height = Room_GetWaterHeight(

src/game/items.h

@@ -18,6 +18,7 @@ void Item_RemoveDrawn(int16_t item_num);
 void Item_AddActive(int16_t item_num);
 void Item_NewRoom(int16_t item_num, int16_t room_num);
 void Item_UpdateRoom(ITEM_INFO *item, int32_t height);
+int16_t Item_GetHeight(ITEM_INFO *item);
 int16_t Item_GetWaterHeight(ITEM_INFO *item);
 int16_t Item_Spawn(ITEM_INFO *item, int16_t object_num);
 int32_t Item_GlobalReplace(int32_t src_object_num, int32_t dst_object_num);

src/game/objects/traps/movable_block.c

@@ -79,7 +79,8 @@ void MovableBlock_Setup(OBJECT_INFO *obj)
 void MovableBlock_Initialise(int16_t item_num)
 {
     ITEM_INFO *item = &g_Items[item_num];
-    if (item->status != IS_INVISIBLE) {
+
+    if (item->status != IS_INVISIBLE && item->pos.y >= Item_GetHeight(item)) {
         Room_AlterFloorHeight(item, -WALL_L);
     }
 }
@@ -110,6 +111,11 @@ void MovableBlock_Control(int16_t item_num)
         item->status = IS_DEACTIVATED;
         FX_DinoStomp(item);
         Sound_Effect(SFX_T_REX_FOOTSTOMP, &item->pos, SPM_NORMAL);
+    } else if (
+        item->pos.y >= height && !item->gravity_status
+        && !(bool)(intptr_t)item->priv) {
+        item->status = IS_NOT_ACTIVE;
+        Item_RemoveActive(item_num);
     }
 
     if (item->room_number != room_num) {
@@ -133,6 +139,10 @@ void MovableBlock_Collision(
 {
     ITEM_INFO *item = &g_Items[item_num];
 
+    if (item->current_anim_state == MBS_STILL) {
+        item->priv = (void *)false;
+    }
+
     if (!g_Input.action || item->status == IS_ACTIVE
         || lara_item->gravity_status || lara_item->pos.y != item->pos.y) {
         return;
@@ -226,6 +236,7 @@ void MovableBlock_Collision(
         item->status = IS_ACTIVE;
         Item_Animate(item);
         Lara_Animate(lara_item);
+        item->priv = (void *)true;
     }
 }
 

src/game/room.c

@@ -590,19 +590,42 @@ int16_t Room_GetWaterHeight(int32_t x, int32_t y, int32_t z, int16_t room_num)
 
 void Room_AlterFloorHeight(ITEM_INFO *item, int32_t height)
 {
-    int16_t room_num = item->room_number;
-    FLOOR_INFO *floor =
-        Room_GetFloor(item->pos.x, item->pos.y, item->pos.z, &room_num);
-    FLOOR_INFO *ceiling = Room_GetFloor(
-        item->pos.x, item->pos.y + height - WALL_L, item->pos.z, &room_num);
+    if (!height) {
+        return;
+    }
 
-    if (floor->floor == NO_HEIGHT / 256) {
-        floor->floor = ceiling->ceiling + height / 256;
+    int16_t data;
+    FLOOR_INFO *floor;
+    ROOM_INFO *r = &g_RoomInfo[item->room_number];
+
+    do {
+        int32_t z_floor = (item->pos.z - r->z) >> WALL_SHIFT;
+        int32_t x_floor = (item->pos.x - r->x) >> WALL_SHIFT;
+
+        if (z_floor <= 0) {
+            z_floor = 0;
+            CLAMP(x_floor, 1, r->y_size - 2);
+        } else if (z_floor >= r->x_size - 1) {
+            z_floor = r->x_size - 1;
+            CLAMP(x_floor, 1, r->y_size - 2);
         } else {
-        floor->floor += height / 256;
-        if (floor->floor == ceiling->ceiling && floor->sky_room == NO_ROOM) {
+            CLAMP(x_floor, 0, r->y_size - 1);
+        }
+
+        floor = &r->floor[z_floor + x_floor * r->x_size];
+        data = Room_GetDoor(floor);
+        if (data != NO_ROOM) {
+            r = &g_RoomInfo[data];
+        }
+    } while (data != NO_ROOM);
+
+    if (floor->floor != NO_HEIGHT / 256) {
+        floor->floor += height >> 8;
+        if (floor->floor == floor->ceiling && floor->sky_room == NO_ROOM) {
             floor->floor = NO_HEIGHT / 256;
         }
+    } else {
+        floor->floor = floor->ceiling + (height >> 8);
     }
 
     if (g_Boxes[floor->box].overlap_index & BLOCKABLE) {

src/game/savegame/savegame.c

@@ -114,10 +114,13 @@ static void Savegame_LoadPostprocess(void)
             }
         }
 
-        if (obj->control == MovableBlock_Control
-            && item->status == IS_NOT_ACTIVE) {
+        if (obj->control == MovableBlock_Control) {
+            item->priv =
+                item->status == IS_ACTIVE ? (void *)true : (void *)false;
+            if (item->status == IS_NOT_ACTIVE) {
                 Room_AlterFloorHeight(item, -WALL_L);
             }
+        }
 
         if (obj->control == RollingBlock_Control
             && item->current_anim_state != RBS_MOVING) {
@@ -179,7 +182,8 @@ void Savegame_PreprocessItems(void)
         ITEM_INFO *item = &g_Items[i];
         OBJECT_INFO *obj = &g_Objects[item->object_number];
 
-        if (obj->control == MovableBlock_Control) {
+        if (obj->control == MovableBlock_Control && item->status != IS_INVISIBLE
+            && item->pos.y >= Item_GetHeight(item)) {
             Room_AlterFloorHeight(item, WALL_L);
         }
         if (obj->control == RollingBlock_Control) {